I had a router Fritz!Box phone 7170. There was a problem with the router and I bought another Fritz!Box 7170. I tried to access the router by using http://192.168.178.1/ and to configure it, using my linux mint PC. After the configuration (internet works) it is not possible for my Linux mint PC to connect to the internet. I checked my network settings, DHCP is used. Skype works, internal connection with my windows machines works, FireFox and Thunderbird don't work. The connection is not possible neither with cable nor with wifi.